From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E284C432C3 for ; Sat, 30 Nov 2019 17:15:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2FAA12082E for ; Sat, 30 Nov 2019 17:15:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=colorremedies-com.20150623.gappssmtp.com header.i=@colorremedies-com.20150623.gappssmtp.com header.b="Is2QVUYZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727104AbfK3RPF (ORCPT ); Sat, 30 Nov 2019 12:15:05 -0500 Received: from mail-wr1-f46.google.com ([209.85.221.46]:34460 "EHLO mail-wr1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbfK3RPF (ORCPT ); Sat, 30 Nov 2019 12:15:05 -0500 Received: by mail-wr1-f46.google.com with SMTP id t2so38695265wrr.1 for ; Sat, 30 Nov 2019 09:15:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=colorremedies-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=sHZd9v4sJbiv+Xitc5Hve6PzvpTBZ7zdoUJg7QkR2BU=; b=Is2QVUYZhW1ujIN8yvoNpFBd9pUjgbuBDA5VKDgm6bNOOBNvITLzokToN1PGvWZHp2 NK3YFzJqcQnfzwvyrPDUgPbY4timEeABCQdmkkZgAW1KpKWSdIYF1xIvhOezCCn1PBnH YSLf9P4gV1nbPA9crNu6s42wA2nMI7AztuntBJGYfgcdzJy2IRaU44wheBAFZcQ8Y5BU f2h79FzKV4Ww0nIMA01ynEO7lSMz7Jyc5AC0IKzEEhN5wBM1NCaZwIezXCrufNrYv7oD ayV+fcKTPHvzV8PRPnqMN2hqWQOv6LPSlD+oiUxacG9AceN0y9TOfnbR+mIgX6p53CLp e6yQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=sHZd9v4sJbiv+Xitc5Hve6PzvpTBZ7zdoUJg7QkR2BU=; b=ADKVUUBmxODFYITlGby4pl66ccpuwEVmbadzSImr9H+RM1WN0lHsn2/acP2yechfHn CgZU1qEr5m6nPXMKPTI+7w1QHq7VHT4m1hvL/N01KQi11qjPT8to8RcfzDqBDZkq76Pd ADFCqmCarP3w89jnkhvSVGOjGUfY+q6iXn31SigLh9hEUH0TfyXNcnYEwntNT+jSPT1b isVrWKISu/rz2o9qrPN0uXLC4hNyHtqONUTjwpx5z8ZPu3mWCt/bkxkEj02EsTv+On0N vkwqJ4MZJwv6Hg/e65hMjT5H3XyPVOYCWAE/aICl3jbrg9He75UEn9pfLTt7rFRVOe0v 1vYQ== X-Gm-Message-State: APjAAAXh0SxE332JbmjSaoudMb48y6uZLXczkZQNf9JJUrycxeJqQPIP 5AKgSlwEO2ePJVLyurLhDqsLXPYEfddMikVmLdyYxw== X-Google-Smtp-Source: APXvYqxWH14sNGOITqC6VfOydnQCH4nJ/47mY9Jy5OB5UV4LoUQttZZdbn5YrXHBUZBfV9mRVg2lq/973PuhHIgvrTg= X-Received: by 2002:adf:ea4e:: with SMTP id j14mr11992084wrn.101.1575134103080; Sat, 30 Nov 2019 09:15:03 -0800 (PST) MIME-Version: 1.0 References: <6bc5b69e-188e-a7b2-e695-bd1bcb6a9ba3@gmail.com> <8a86c7ef-39ab-7c35-f39b-e05ab7543a11@gmail.com> In-Reply-To: <8a86c7ef-39ab-7c35-f39b-e05ab7543a11@gmail.com> From: Chris Murphy Date: Sat, 30 Nov 2019 10:14:47 -0700 Message-ID: Subject: Re: GRUB bug with Btrfs multiple devices To: Andrei Borzenkov Cc: Chris Murphy , Goffredo Baroncelli , Btrfs BTRFS Content-Type: text/plain; charset="UTF-8" Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Sat, Nov 30, 2019 at 10:02 AM Andrei Borzenkov wrote: > > GRUB is normally using hints - grub-install (and grub-mkconfig) tries to > guess firmware device name. At boot time grub tries to access hinted > device first, if it succeeds, it does not try anything else. With second > btrfs partition grub needs to find second device at boot time so it now > probes everything and hits those vendor media devices. > > At least this explains what you see as well as ... > > > Last time this > > happened, all I did was remove the 2nd device and the problem went > > away. > > ... this. Ahhh, that makes complete sense. So it is Btrfs multiple device related, but not a bug in btrfs.c per se. > > If you go in grub shell in this state (without errors), do you see those > ghost devices? Uncertain. My vague memory recall is that yes they are there, because I found their existence strange and different compared to pre-GRUB 2.02 where on this same system I'd see only either hd0 or hd1 (one without the other), along with cd0. But something changed either with a firmware update from Apple, or GRUB, that resulted in additional GRUB devices, hd2, hd3, hd4, hd5. > > I'm ready to try that again (remove the 2nd device) and see if > > the problem goes away, but has enough information been collected about > > the present state? > > > > > > If you are reasonably sure that all errors are related to those phantom > devices - I would say yes, the reason for these phantom devices to exist > is already clear. I'll give it a shot in a bit. -- Chris Murphy